The Global Positioning System (GPS) comprises a space-based satellite navigation system, which was implemented by the United States, and which provides very accurate and reliable positioning, navigation, and timing services. System development began in secret in the early 1970s by the U.S. Air Force, with insertion of the first satellite into orbit in 1978. But in 1983, after a Soviet interceptor aircraft shot down a civilian Korean Air Lines commercial aircraft that crossed into prohibited airspace due to a navigational error, President Reagan declassified the project, and announced that it would be made available for civilian use once completed. Full operational capability was achieved in 1995, and today, a continually updated array of between 24-32 satellites, in distinctive orbits about the earth, permits a precise three-dimensional location (latitude, longitude, plus altitude) and time determination for a user anywhere in the world-wide. In general, visibility at a position on the Earth's surface of at least four satellites permits normal use of the broadcast signals.
A user's GPS receiver, the third element in the GPS triad, with the first two being space-based satellites and a ground-based satellite control system, has traditionally provided the ability to obtain directional guidance to a destination. One invention providing such ability through the broadcast GPS signals is shown by U.S. Pat. No. 5,177,685 to Davis for “Automobile Navigation System Using Real Time Spoken Driving Instructions.” In the Davis invention, the driver inputs information to describe a desired destination The vehicle location system accepts input from a position sensor which continuously measures automobile movement (magnitude and direction), and using this information in conjunction with the map database, the system's algorithm calculates a route. Based on the current position of the automobile and the route, a discourse generating program composes appropriate driving instructions to the destination.
An improvement upon Davis is shown by U.S. Pat. No. 5,933,100 to Golding, which includes a cellular telephone in the automobile for communicating with a central database to obtain traffic updates in order to provide optimum route selection that is weighted to include the dynamic travel time information.
The availability of GPS signal information has also pawned a number of various related inventions, such as U.S. Pat. No. 7,145,507 to Luo for a “Vehicle Locating System Using GPS.” The Luo invention includes a car that is equipped with a GPS receiver and a transceiver to transmit the car's location, on demand, to a user's GPS receiver retained as a key-ring fob, which also has a transceiver for receipt of the car's transmitted location, and provides correlation of the car's position relative to the user's position. The Luo invention, while assisting an owner in finding his car, does not significantly expand usage of the basic GPS functionality, but points to another use, which is its application by a pedestrian visiting a foreign city, or an outdoor hiker.
The latter has helped to revolutionize games that have been played for years in a simplistic form by children and adults—that of a treasure hunt. While the traditional Easter egg hunt may occur predominantly in a private home or yard, the modern “treasure hunt” occurs on a grander scale, as shown by U.S. Pat. No. 5,942,969 to Wicks, where players are directed from landmark to landmark on a course by receiving information and clues from a paging system, which may also be used to track the successful navigation of the course by each participant. The proliferation of GPS devices has advanced the game playing to use such devices. U.S. Pat. No. 6,320,495 to Sporgis discloses generally a treasure hunt game utilizing a GPS equipped wireless communications device, where players are given clues or directions for a predetermined treasure hunt route, based on their GPS location. The game has become popularly known under the trademarked name of “Geocaching,” which is held by the private company called “Groundspeak.” The company's game-centered web-site—www.geocaching.com—now boasts over one million “active caches” or containers located in over 100 countries and on all continents, including Antarctica. Some advancement and customization for the game has been proffered by U.S. Pat. No. 6,691,032 to Irish, for “System and Method for Executing User-Definable Events Triggered through Geolocational Data Describing Zones of Influence.”
Some attempts have been made to conceive devices to assist users in journeying to distant places, based on a series of waypoints, whether for business uses, for Geocaching adventures, or just personal exploration. Some examples are shown by U.S. Pat. No. 6,810,323 to Bullock for “System and Method for Storing and Using Information Associated with Geographic Locations of Interest to a Mobile User”; and U.S. Pat. No. 7,565,240 to Tomizawa for “Navigation device, method, and program.”
However, despite the prolific number of GPS devices and related patents heretofore developed and disclosed, there remains a lack of interactive capability and customization that may be incorporated into a device with GPS data supplied therein. The prior art also lacks sufficient capabilities to assist in navigation beyond standard highways and byways. This invention discloses such capability in the form of customizable off-road navigation software for Pocket PC-type devices.